diff -Nur pinfo-0.6.10/src/parse_config.h pinfo-0.6.10-new/src/parse_config.h
--- pinfo-0.6.10/src/parse_config.h	2006-03-10 03:44:48.000000000 +0800
+++ pinfo-0.6.10-new/src/parse_config.h	2021-08-03 15:53:00.000000000 +0800
@@ -85,7 +85,7 @@
 colours;
 #endif /* NO_COLOR_CURSES */
 
-int use_manual;
+extern int use_manual;
 
 int parse_config (void);
 int parse_line (char *line);